<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        * {
            margin: 0;
            padding: 0;
        }

        html,
        body {
            overflow: hidden;
        }

        .webgl {
            position: fixed;
            top: 0;
            left: 0;
            outline: none;
        }
    </style>
</head>

<body>
    <canvas class="webgl"></canvas>
    <script>
        let gVertShader = `
uniform float uTime;
uniform float uSize;

attribute float aScale;
attribute vec3 aRandomness;

varying vec3 vColor;

vec2 fade(vec2 t)
{
    return t*t*t*(t*(t*6.0-15.0)+10.0);
}

vec4 permute(vec4 x)
{
    return mod(((x*34.0)+1.0)*x, 289.0);
}

float cnoise(vec2 P)
{
    vec4 Pi = floor(P.xyxy) + vec4(0.0, 0.0, 1.0, 1.0);
    vec4 Pf = fract(P.xyxy) - vec4(0.0, 0.0, 1.0, 1.0);
    Pi = mod(Pi, 289.0); // To avoid truncation effects in permutation
    vec4 ix = Pi.xzxz;
    vec4 iy = Pi.yyww;
    vec4 fx = Pf.xzxz;
    vec4 fy = Pf.yyww;
    vec4 i = permute(permute(ix) + iy);
    vec4 gx = 2.0 * fract(i * 0.0243902439) - 1.0; // 1/41 = 0.024...
    vec4 gy = abs(gx) - 0.5;
    vec4 tx = floor(gx + 0.5);
    gx = gx - tx;
    vec2 g00 = vec2(gx.x,gy.x);
    vec2 g10 = vec2(gx.y,gy.y);
    vec2 g01 = vec2(gx.z,gy.z);
    vec2 g11 = vec2(gx.w,gy.w);
    vec4 norm = 1.79284291400159 - 0.85373472095314 * vec4(dot(g00, g00), dot(g01, g01), dot(g10, g10), dot(g11, g11));
    g00 *= norm.x;
    g01 *= norm.y;
    g10 *= norm.z;
    g11 *= norm.w;
    float n00 = dot(g00, vec2(fx.x, fy.x));
    float n10 = dot(g10, vec2(fx.y, fy.y));
    float n01 = dot(g01, vec2(fx.z, fy.z));
    float n11 = dot(g11, vec2(fx.w, fy.w));
    vec2 fade_xy = fade(Pf.xy);
    vec2 n_x = mix(vec2(n00, n01), vec2(n10, n11), fade_xy.x);
    float n_xy = mix(n_x.x, n_x.y, fade_xy.y);
    return 2.3 * n_xy;
}


void main(){
    vec4 modelPosition = modelMatrix * vec4(position, 1.0);

    //spin here
    float angle = atan(modelPosition.x, modelPosition.z);
    float distanceToCenter = length(modelPosition.xz);
    float angleOffset = (1.0 / distanceToCenter) * (uTime*0.2);
    // angle-= angleOffset+uTime/distanceToCenter/2.0;
    // angle-= 100.0-10.0*(uTime/1.0*(distanceToCenter*0.02));
    // angle-= sin(angleOffset+uTime)/(distanceToCenter * cnoise(aRandomness.xz));
    angle-= sin(angleOffset+uTime)/distanceToCenter + cnoise(aRandomness.xz)*cnoise(aRandomness.xy);
    
    modelPosition.x = cos(angle)* distanceToCenter+ cnoise(aRandomness.xz)*cnoise(aRandomness.yz);;
    modelPosition.z = sin(angle)* distanceToCenter+ cnoise(aRandomness.xz)*cnoise(aRandomness.xy);;
    // modelPosition.y = sin(aRandomness.y) * 11.0+abs(2.0/distanceToCenter)-10.0;
    modelPosition.y = (aRandomness.y*aRandomness.x) * 1.0-(aRandomness.y*aRandomness.y);

    modelPosition.xyz += aRandomness/12.0;
    
    vec4 viewPosition = viewMatrix * modelPosition;
    vec4 projectedPosition = projectionMatrix * viewPosition;
    gl_Position = projectedPosition;
    //
    gl_PointSize = uSize*aScale;
    gl_PointSize *= ( 1.0 / - viewPosition.z );

    vColor = color;
}
`;

        let gFragShader = `
varying vec3 vColor;

void main()
{
    // //Disc
    // float strength = distance(gl_PointCoord, vec2(0.5));
    // strength = step(0.2, strength);
    // strength = 1.0-strength;
    
    //Diffues
    // float strength = distance(gl_PointCoord, vec2(0.5));
    // strength *=2.0;
    // strength = 1.0-strength;
    
    // //Diffues
     float strength = distance(gl_PointCoord, vec2(0.5));
     strength = 1.0-strength;
     strength = pow(strength, 7.0);

    vec3 color = mix(vec3(0.0), vColor, strength);
    gl_FragColor = vec4(color,1.0);
}

`
    </script>
    <script type="module" src="./index.js"></script>
</body>

</html>